The goal of this project is to develop a rapid, cost-effective screening method for detecting all mutations in the p53 gene. The goal of Phase I is to optimize conditions for direct genomic sequencing of PCR products from human tumor cell lines. Both malignant mesotheliomas and sarcomas have been shown to be induced by different chemical carcinogens. Forty malignant mesothelioma and sarcoma cell lines, for which mutations have previously been detected, will be studied. These samples will allow the determination of the efficiency and applicability of multiplex sequencing for scanning genomic DNA for point mutations. Phase II will involve the study of large numbers of malignant mesotheliomas. These experiments will determine if specific codons or exons in p53 are mutated in malignant mesotheliomas and if there is any correlation between the site of mutation and the clinical outcome. Overall, this research will demonstrate the feasibility of using a multiplex sequencing approach for mutation scanning in human clinical samples. While the specific aims of this project are to determine the location of p53 mutations in malignant mesotheliomas, the methods developed will allow one to screen other forms of cancer for mutations in p53 as well as in other genes.